The gsod package (https://github.com/databrew/gsod#gsod-tools-for-using-noaa-global-surface-summary-of-the-day-data) - which I wrote and maintain - is a bit too simple for what you’re trying to do. The “sod” part of “gsod” stands for “summary of the day”. In other words, all the data is at the daily level (and there is nothing more granular than that).
That said, we can reverse-engineer the values a bit. For example, gsod offers an “average” temperature, a “max”, and a “min”. For 2017, for all 12,835 weather stations, 0% of them report the “average” temperature as the mid-point between the max and min more than 3% of the time. In other words, it’s almost certain that they are averaging hourly temperatures (or something less regular, more/less granular, etc.) and calculating the average that way.
Here you go. The below map shows the difference between the reported “average” and the midpoint method (the former minus the latter) for each station. It displays the average of this difference for the entirety of 2017.
The above map is a bit hard to use, since it’s static, and there are more than 12,000 points to look at. It might be better to use an interactive map, so that we can zoom in and explore (each dot is a weather station, clicking on it shows the details):